Delivery mechanism for printing machines



Jan. 18, 1927. E w. WRGHT DELIVERY MECHANISM FOR PRINTING MACHINES 11 192 Jan 7 F. w. WRIGHT DELIVERY MECHANISM FOR PRINTING MACHINES 2 Sheets-Sheet 2 Filed June 5. 1926 Patented Jan. 18, 1927.

UNITED STATES FRED WESLEY WRIGHT, OF LEEDS. ENGLAND, Assienoaor. ONE-[FOURTH ro'rHoMAs rnnivx ELSWQRTH, onnroma'rrr T0 PERCY BARKER, ruin ONE-FOURTH T0 GEORGE MANN AND COMPANY LIMITED, ALL or A'RoHF nLn wort gs, LEEDS,- Eno- DELIVERY MECHANISM FOR ERIN-TING MACHINES.

Application filed June v 5. 1926, Seria1 No. 113,949, and in GreatBritaiaJuly 2, 1,925.

This invention relates to printing ma- .chines of the type having an impression cylinder and delivery chains receiving a sheet direct from the impression or take-oil cylinder and driven throughout the working cycle by a single gear train. Thepresent invention consists in a machine of the above, type in which the single gear train driving the delivery chains is controlled by a timed cam so that thespeed of the delivery chains is equal to the uniform peripheral speed of the impression or takeoff cylinder during the take-off portion of the working cycle and is less than such peripheral speed during the remainder of 'thefycle.

The invention will now be described by way of example with reference to the accom pa'nying drawings, in which Figure 1 shows a timed cam suitablefor an epicyclic gear delivery mechanism;

' Figure 2 shows the delivery mechanism driven by a rack and pinion gear controlled by the timed cam with the casing in section;

Figure 3 is an end view of a portion of Figure 2 with the casing in section, and

Figure ishows the delivery mechanism driven by sliding helical gears.-

Accord ng toone form of the invention as appliedby way of example to a delivery mechanism driven by an epicyclic gear as described in the specification of Patent No. 1,537,594 dated the 12th of May, 1925, the timed cam is formed as shown in Figure 1, andfor the sake of convenience may be considered as divided into five portions, the first portion beingdesignated as A to B. At position A the chains will momentarily be running at their average speed and from position A to position B the cam is so formed "as to speedup the chains. From position B to position C the cam groove takes the form of an Archimedean spiral and occupies about two-thirds of the, whole circumference. The chains'will then be running at a uniform speed equal to the peripheral speed of the ,t'ake-off cylinder for taking ofl' the sheet.

' Front position C to position I) the chains .will return to their average speed. From pos1tio n D to position E the chains will 'slow down to their minimum speed for depositing a sheet and from position E to position A return to theiraveragespeed.

The speed of-the chains is thus'not increased above the uniform take-off speed at any point of the cycle.

According to a modified-form of the. invention diagrammatically illustrated in Figure2, applied by way of example to anoflset rotary printing machineinwhich the impression cylinder, 1, makes two revolutions per impression,--the shaft, 2, on which the IIIIPIGSSlOII cylinder is mounted is provided with a pinion, 3, engaging with p a gear wheel, 1-, mounted upon a camshaft, 5, the gears being in the ratio of 1 to .tvso that the camshaft rotates halfarevolution for each impression. The ca-mshaft, 5, is pro vided with two similar cams, 6, 7,:the centre line of whichis only shown, having .paths set at 180 apart. Two rocking levers, 8, 9, are mounted upon a common pivot, 10, the ends, 11, 12, ofthe levers being-provided with suitable rollers or the like engaging respectively in the appropriate cam grooves, 6 land 7. The other arms of the levers are considerably longer and are provided with links, 13,14, which are pivotallyconnected to two rack bars, 15, 16,'situated sideby side and sliding in a cage, 17-. The two rack bars. engage with two pinions, 18, 19, mounted I loosely upon the shaft, 20, and the pinions are provided with projections, 21, 22, upon which are mounted the pawls, 23, 24:, engaging with notches or shoulders, 25, 26, on the boss or hub, 27, fixed by means of keys or the like to the shaft, 20; The two shoulders on the 7 boss are situated exactly at 180 apart.

Also keyed to the shaft, 20, is a gear wheel,

28, which drives-the delivery chainwheel, 29,

through a suitablegear train, 30,31, 32. The chains'are tl usdr'iven through the rack and pawls and their speed is at all times depend ent upon the shape of the cams. Since the cams as well as the shoulders are arranged at 180 apart, one rack bar drives on its forward stroke while the other rack bar returns idle on its backward stroke and vice versa.

The cams may be considered as divided into six portions the first portion being desig nated asa'to I); I

When the roller, 12, on the end of the lever, 9, is at the point, a, of the cam, 7, the lever begins to move from left to right of the figure, increasing the speed of the rack, 16. At the point, 5, the rack, 16, commences to drive the gear which is relinquished by the rack, 15, when the roller, 11, arrives at the point, e, on the cam, 6. From Z) to c the speed of the chains is increased until at 0 they are moving at the speed of the delivery or take-off cylinder. From 0 to d the speed of the chains is uniform, the cam path being an Archimedean spiral. From d to e the chains slow down and at e the drive is transferred to the other rack, 15, the roller, 11, being at the point, 7), on the cam, 6. From 6 to f the rack, 16, moves forward idly and from f to a the rack returns to the starting position.

The extreme limits of travel of the racks occur when the rollers are at the points a, a, and f, f of the cams.

The path of the cam which is used for the constant speed equal to the peripheral speed is an Archimedean spiral, but the other portions of the cam path may have any suitable form to accelerate and retard the speed of the chains as desired.

According to another form of the invention as illustrated in Figure 4, the timed cam, 40, operates a bell crank, 41, 42, which is connected by a link, 43, to a double-ended lever, 44, pivoted at 45. The lever, 44, is provided with a block or the like 46, running in a groove, 4?, on the pinion, 48, which slides by means of a spline or feather on the shaft, 49, which is driven by suitable gearing from Elie shaft, 2, carrying the impression cyliner, 1. r

The sliding pinion, 48, is provided With helical teeth which engage a wheel, 50, and drives through suitable gearing the chain wheel, 51. i

The cam, 40, reciprocates the pinion, 48, and gives the variable motion to the chain. The shape of the cam is as shown in Figure 1 and the uniform speed is obtained by the portion of the cam B to C which is an Archiinedean spiral, the retardation and acceleration of the chains by the portions, AB, DE and EA, of the cam having any suitable form, the speed of the chains never exceeding the peripheral speed of the impression or take-oil cylinder.

Other mechanism using a timed cam may b d without exceeding the scope of the invention.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:-

1. The combination in a sheet-delivery mechanism for printing machines, of a takeoff cylinder rotatable at a uniform peripheral speed, delivery chains in. operative takeoff relation to said cylinder, a cam in timed relation to said cylinder and means depend.- cnt on said cam for driving said delivery chains at a speed equal to the Peili'lllBl'Hl speed of said take-elf cylinder during one period of the working cycle and at varying speeds less than said peripheral speed during the balance of said cycle.

2. The combination in a sheet-delivery mechanism for printing machines, of a takeoff cylinder rotatable at a uniform peripheral speed, delivery chains in operative takeoff relation to said cylinder, a cam in timed relation to said cylinder, said cam having an operative portion formed as an Archime dean spiral, andmeans dependent on said spiral portion of said cam for driving said delivery chains at a speed equal to the peripheral speed of said take-off cylinder during one period of the working cycle and dependent on parts of said cam other than said spiral portion at varying speeds less than said peripheral speed during the balance of said cycle.

3. The combination in a sheet-delivery mechanism for printing machines, of a takeoff cylinder rotatable at a uniform peripheral speed, delivery chains in operative takeoff relation to said cylinder, a cam in timed relation to said cylinder and means dependent on said cam for driving said delivery chains at a speed equal to the peripheral speed of said take-off cylinder during one period of the working cycle and at varying speeds less than said peripheral speed during the balance of said cycle, said driving means including a lever operated by said timed cam, a toothed element forming one of a train driving said delivery chains and an other toothed element in mesh With said first-mentioned toothed element and reciprocated by way of said lever.

4. The combination in a sheet-delivery mechanism for printing machines, of a take-off cylinder rotatable at a uniform pcripheral speed, delivery chains in operative takeoff relation to said cylinder, a cam in timed relation to said cylinder and means dependent on said cam for driving said de livery chains at a speed equal to the peripheral speed of said take-oil? cylindci' during one period of the working cycle and at varying speeds less than said peripheral speed during the balance of said cycle, said driving means including a train of gearing op cratively connecting said take-oil cylinder and said delivery chains, said train having a toothed element and means controlled by said cam for reciprocating said toothed element.

5. The combination in a sheet-delivery mechanism for printing machines, of a takeolf cylinder rotatable at a uniform peripheral speed, delivery chains in operative takeoff relation to said cylinder, a cam in timed relation to said cylinder and means dependlll) said delivery chains, said train having a spindle and a Worm splined thereto and 10 means controlled by said cam for reciprocating said Worm on said spindle.

In testimony whereof I have signed my name to this specification.

FRED WESLEY WRIGHT. 

